1. Field of the Invention
The present invention relates to an image converting apparatus suitable for a special effect image editing apparatus for performing various processes for an image of an input video signal, in particular, to an image converting apparatus for converting an input video image into an image with various metallic lusters.
2. Related Prior Art
A special effect image editing apparatus performs various processes for an image of an input video signal. Typical special effect processes performed by a conventional special effect editing image apparatus include enlarging an image, reducing an image, moving an image, rotating an image, emphasizing the contour of an image, shading off an image, color-inverting an image, and color- converting an image. Such a special effect image editing apparatus is used to generate an impressive image.
In addition, a special effect process for changing the texture of a substance is desired. In other words, assuming that there is a doll made of ceramic, even if the colors of the image of the doll are changed, the contour thereof is emphasized, or the image is shaded off, the texture of the ceramic is not substantially changed. When reflected light of a metal can be represented for such an image, the image of the doll made of ceramics can be converted into an image of a doll made of gold or silver. Thus, when a special effect process for changing the texture of a substance can be performed, an image that has a completely different impression from the original image can be reproduced. Consequently, a very interesting image can be generated.
A special effect process for converting an input image into an image with various metallic lusters requires calculations for the image conversion. It is necessary to analyze reflected light of the metal and perform calculations corresponding to the analyzed results. To do that, a model of reflected light for metallic lusters is created. With the model, the calculation process for generating metallic lusters is considered. However, a model of reflected light is represented in three dimensions. On the other hand, a conventional video signal is represented in two dimensions rather than three dimensions. Thus, it is difficult to perform a process for converting a video signal into an image with a metallic luster using the model of the conventional reflected light.
In addition, since there are various patterns as input images, even if the process for generating a metallic luster is performed for an input image, a proper effect may not take place. In addition, in the case that the variations in the brightness of the input image is small, the image may be equally colored. Thus, in this case, a metallic luster may not take place. In contrast, when the variations in the brightness of the input image is large, the resultant image glares and thereby appears as an unsmooth image. Consequently, when the input signal is a video signal, it should be processed corresponding to the pattern.
Therefore, an object of the present invention is to provide an image converting apparatus for converting an image of an input video signal into an image with a metallic luster and representing a metallic luster with parameters designated corresponding to the input image.